Grease guns have been employed in a wide variety of environments. Generally, grease guns are used to inject grease under pressure through specialized fittings, called Zerk fittings, to lubricate bearings, gears and other moving parts. Commonly, grease guns can be powered manually via a lever or trigger pump or automatically via air or electric power and accept standard grease cartridges which may be filled with nearly any weight of grease from lightweight lubricants to heavy axle grease. Replacing the cartridge consists of inserting a new cartridge, priming the gun and bleeding off trapped air.
In use, the head of the grease gun is unscrewed from its barrel by twisting it counterclockwise. A handle which is spring loaded by virtue of an interior spring assembly (illustrated by element 15 of FIG. 1) is retracted into the barrel and locked in place by virtue of a notch in the rod and detent at the base of the barrel. The spent cartridge is removed by pulling it out through the top end of the barrel and replaced by inserting a new cartridge into the barrel, open end down. The head is then reapplied to the barrel and the rod released and pushed to remove trapped air. Thereupon, the head is tightened and a bleeder valve is pressed to release any remaining air. A movable lever or alternative means is used to initiate grease flow out of the hose. or coupler fitting smoothly.
Due to the environment in which grease guns of this type are employed, it is common to experience problems with the threaded connection between the head assembly and threads of the barrel. Users of these types of grease guns often find it necessary to repeatedly remove the head assembly from the barrel and when debris and foreign matter clog threads, these threads as well as the adjoining threads on of the head cap assembly bind which, in extreme cases, can render the grease gun useless.
It is thus an object of the present invention to provide an adapter between the grease gun barrel and head cap assembly which would obviate the need to threadably connect the head cap assembly to the barrel.
This and further objects will be more readily apparent when considering the following disclosure and appended claims.